GPT-3.5 Turbo was released by OpenAI on March 1, 2023, as a lightweight model in the GPT Terra line.
GPT-3.5 Turbo brought the model behind ChatGPT to OpenAI's API at $0.002 per 1K tokens, 10x cheaper than OpenAI's existing GPT-3.5 models.
Compared with GPT-3.5 · comparison chosen by OpenAI
Costs developers a tenth as much as OpenAI's earlier GPT-3.5 models
Price per 1M tokens — what developers pay, input / output
$2 / $2
▲ launch price, $0.002 per 1K tokens · 10x cheaper than OpenAI's existing GPT-3.5 models
Every Monday, only when something shipped: the AI models that came out, what each one changed, and which lines are due next.
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GPT-5.6 Terra is the current model in this line. The card shows how long it has been since the last release against the line's usual gap and its recent ones — the rhythm, not a date.
Latest: GPT-5.6 Terra · Jul 9, 2026
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